CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $)
In Thousands, except Share data, unless otherwise specified
Dec. 31, 2013
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
CONSOLIDATED BALANCE SHEETS        
Accounts receivable, allowance for doubtful accounts $ 13,646 $ 16,386 $ 4,002 $ 3,698
Common shares, par value (in dollars per share) $ 0.00139482 $ 0.00139482    
Common shares, authorized (in shares) 120,000,000 120,000,000    
Common shares, issued (in shares) 85,503,321 88,312,068    
Common shares, outstanding (in shares) 85,503,321 88,312,068